XF 1.5 Unexpected Database Error.

I updated my forum to the latest xenforo update few days ago and added few addons to the forum, days after my site fails to load with "unexpected database error" displayed. I contacted my host company and help to restore the forum but some data and all the new update was lost.

I tried to reinstall the addons and xenforo updates again last night but to my surprise, the same problem still reoccur.

I will like to ask expert with experience on what to do to fix this problem pls.